Metal cutting tools used in milling operations, including cutting inserts which are removably secured in a cutting body, have long since provided a suitably hard material, i.e. cemented carbide, in the vicinity of the cutting edge, where the cutting body, manufactured from a less hard material, is reusable following the disposal of a worn or damaged cutting insert.
Cutting inserts are clamped within insert receiving pockets located on the periphery of the tool body, for holding and supporting cutting inserts in both axial and radial directions during operation (e.g., milling operation).
U.S. Pat. No. 3,541,655 issued to Stier, and entitled “Indexable and Reversible Cutting Inserts”, is directed to a cutting insert with two parallel identical uneven polygonal end faces. The end faces are rotated with respect to one another. A trapezoidal side face extends between each side of one of the polygonal end faces and a respective side of the other end face. Each two adjacent side faces are formed of two opposite trapezoids. Each trapezoidal side face forms an acute angle with one of the end faces, while forming a complementary obtuse angle with the other end face.
U.S. Pat. No. 7,037,051 issued to Wermeister, and entitled “Cutting Insert for Turning and Milling”, is directed to a cutting insert with first and second polygonally-shaped main faces arranged substantially parallel to one another. A side face structure interconnects the first and second main faces to define a peripheral edge. The main faces include projections extending towards the peripheral edge. Each projection is formed by a portion of the first main surface, defining a relief surface; a portion of the side face structure, defining a rake surface; and a portion of the peripheral edge, defining a cutting edge. The cutting insert includes support surfaces defined by a portion of the second main face, and by portions of the side surface structure other than the rake surface.
U.S. Pat. No. 5,957,629 issued to Hessman, and entitled “Fine Milling Cutting Insert”, is directed to a double-sided milling cutting insert. The insert includes two parallel main surfaces which are turned 90° relative to each other. Each main surface includes four operative cutting corners. In each cutting corner there are two bevelled surfaces which are angled relative to the plane of the main surface. Further, four side surfaces of the insert are angled extending between the main surfaces.
U.S. Pat. No. 4,294,566 issued to Boone, and entitled “Eight Edge Positive Chip Control Insert”, is directed to a cutter insert with eight positive cutting edges and a rectangular prismatic configuration. The insert has a pair of opposed primary faces, and four rectangular side faces each having a pair of coplanar, flat lands in opposite corners thereof, for positive location and clamping of the insert. Each side face also has a laterally opposed pair of positive beveled facets formed therein, and intersecting the respective primary faces in an inward slope to define neutral cutting edges for the insert. An elongated groove extends intermediate the beveled facets of each side face parallel to the neutral cutting edges.
It is an object of the present invention to provide an improved indexable reversible cutting insert and cutting tool therefor, the cutting insert having a plurality of cutting edges, which may be employed in a positive axial rake and a negative radial rake relation to a work piece.